


The Tunnel

by PineWreaths



Category: Gravity Falls
Genre: F/M, NSFW, pinescest - Freeform
Language: English
Status: Completed
Published: 2015-10-02
Updated: 2015-10-02
Packaged: 2018-04-24 10:10:01
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 9
Words: 18,269
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4915474
Author URL: https://archiveofourown.org/users/PineWreaths/pseuds/PineWreaths
Summary: <blockquote class="userstuff">
              <p>Dipper finds out how deeply Mabel's feelings for him truly run during an innocent trip to the water park. (My first fanfic story!)</p>
            </blockquote>





	1. Chapter 1

_“Come oooooon Dipper! Watermania awaits!”_

Mabel’s pleading cry echoes up the hallway, and for at least the third time in the last five minutes Dipper looks down at his two-sizes-too-small, faded mustard-colored swim trunks, looks up at his reflection in the mirror, and sighs. She’s been anxious to go to the park for weeks now, and now he seriously regrets not tagging along with her last weekend when she tried to get him to tag along on a “Watermania shopapalooza” at the mall.

The contents of the trunks’ pockets lay emptied across the desk: Skipping rocks, a worn calculator, and of course a trio of chewed-on pencil nubs. His eyes are caught by a paper-mache book next to the pencils, the size of a matchbox. He smiles; It’s a tiny replica of Journal 3, the little number smudged from age and mushing up against his hands and the other pocket contents. Was it really two-no, three summers ago when they were last over there?

Dipper picks it up, turning it over and snorting out a smile as some of his sister’s trademark glitter detaches to infect his messy desk. He starts to brush at it before stopping, recognizing the futility of cleaning it while stacks of empty noodle cups and a hoard of flatware and dishes lie stacked precariously on old textbooks.

He stares at the little journal, still smiling absently, remembering Mabel’s broad grin and the hand-made tissue paper wrapping she had first presented it in; It was the Sunday comics, but she had pasted pictures of them over all of the heroes, and the newspaper’s mugshots of Gideon over more than a few of the monsters. He had loved it then, and loved the miniature Journal even more. “It was _supposed_  to be a little one you could actually open and write in, but I kinda derped with the glue and went a bit overboard,” she had said, her tone falling slightly before renewing with a triumphant “Now it’s a awesometastic keychain!”

His shoulders hunch forward a bit, and the smile fades. He had kept that wrapping paper, celebrating their official transition into the unknowable realm of Teenagerhood, and promised that he was going to use the journal as a keychain as soon as he actually had keys to put on it. But the wrapping paper had probably been discarded in one of his mom’s past scourings of his room, and the journal had been forgotten with the unused swim trunks. They hadn’t been back to Gravity Falls since that summer, when their parents insisted that they spend time here at home instead of there, at the place that felt more alive and like home than ‘home’-home was now.

“OI, EARTH TO DIPPINGSAUCE!”

Dipper let out a shriek, dropping the tiny journal with a clatter on the floor and nearly falling backwards over his chair. Mabel was standing in his doorway, one hand on her hip, and the other making an ‘Earth to Dipper, come in Dipper’ motion. He took a second to slow his suddenly-racing heartbeat, before clearing his throat. “Uh, heh, sorry Mabes. I was trying to figure if there was an angle these shorts  _didn’t_  look like an abomination to common decency.”

She leans back on his door frame, glitter shimmering against her pastel-blue tank top, with a faded unicorn dancing under a rainbow with the words  _Magical!_ emblazoned in a smattering of even more glitter. She was wearing an inflatable swimming ring, bright yellow and with the head of a duck jutting from the front like the prow of a ship. The duck had what Dipper could only see as a surprised expression, likely at the injustice of being used as a flotation device. Below that, her bare legs led to a pair of purple sharpie-patterned sandals, emblazoned with a neon-green ‘M’ and ‘P’ on the tops of the straps.

“Well, the Mabester is quite a renowned expert on fashion,” she says, looking up to the ceiling in thought while tapping her chin with a finger before glancing back down at him. “Lemme take a look-see. Worst case, Dad might have some of his old trunks you could-”

He cuts her off with a hurried shake of his head. Their dad had a penchant for incredibly short-shorts, and Dipper was already feeling self-conscious enough. Mabel gave him a solemn, knowing nod, before looking him over, making little “Hmm, hmm, hmmmm, mhm, hmmmmmm” noises as she assesses his fashion choices..

He caught a glimpse of a bright-red swimsuit strap under the pastel tank top before Mabel shifted again, this time to peer at him while pursing her lips, fingers stroking an invisible goatee while she scrutinized his attire. She leans back and continues looking at his shorts, and he gets another flash of red swimsuit beneath the surprised duck face. He swallows, and again tries to stamp down the thoughts that pop up like little malevolent soap bubbles.

The thoughts had cropped up occasionally, the last year or two more than most, but for the most part he’s been staying on top of keeping them squelched and their physical reactions minimized. It doesn’t help that he was worried that he and Mabel’s twin telepathy might pick up on that, and that anxiety is made worse by Mabel seeming to wear red every time the evil bubble thoughts bubble up. The color of her swimsuit today was seemingly mocking him, and the heat began to rise in his cheeks, attempting to turn his face the color of her suit.

Today, the bubbles are proving un-poppable, and he can feel himself starting to stiffen and tent his trunks.  _Oh god, not now, not while she’s looking right at it. Seriously, brain, you’re going to go and pull this on my NOW of all times?_  He cursed his evil body, and began frantically trying to picture Grunkle Stan naked, but to no avail.

He can see her gaze start to drop lower, no doubt seeing the pronounced bulge, and he can feel his stomach drop as his ears start to burn as the heat spreads up from his cheeks. He squelches his eyes shut, not wanting to look at her when she inevitably says-

“You kept it!”

_Huh?_ He wasn’t expecting that, and he hears a rush of movement and a quiet thump.

He peeks an eye open and almost jumps back again, a little “gah!” escaping nonetheless. Mabel is on her knees right next to him, her gaze focused on the floor. His breath catches as he realizes her head is right next to his shorts, and less than a few inches from his-

_No. Bad thought; Quit tempting the telepathy already._

She darts out her hand, and grabs the miniature journal, spare glitter from her poofy furry bracelet re-infecting the keychain with the herpes of craft supplies. “Well, hello you little rascal you,” she says, turning over the journal as she quickly inspects it for damage.

She gets to her feet, as Dipper begins to sigh in relief, and Mabel thrusts the journal towards him, a wide grin pleading with him as he chuckles and pulls his keys out from a pocket of his rancid jeans in the corner. He finishes sliding the ring with his other keys, and is about to slip it into his swim-shorts pocket when he looks up to see Mabel giving him a pout.

“What? What’s wrong?” he says, before she pointedly looks at the Rumble McSkirmish keychain he already had on there and back to him.

“Really, Mabel? But that’s my favori-” His feeble protest is cut off by Mabel turning the Sad-o-meter to 11, her puppy-dog eyes making his stomach do a floop, and can feel some of the flush from his face redirect itself southward, and again he begins to harden and-

_Nostopitalready._

He gives a long suffering sigh aloud, and threads the Fight Fighter off of the ring, leaving the Journal along with the house, car, and school locker keys. Tossing Rumble off onto the cover of _Trigonometry: 1984 Edition_ , he begins to ask “There, is that bett-”

Before he can finish, Mabel has bounded over to grasp him in one of her bone-crushing megahugs, making a happy “Squee!” noise the entire time, and rocking him side-to-side. He used to hate it when she did this, since it tended to remind him of his own noodly arms, but now he just kind of accepts it.

Dipper smiles, but suddenly has a jolt of terror as he feels a wonderful bump of her smooth leg against his crotch.

_No, no, nononono-_

It happens again as Mabel twists slightly side-to-side with her megahug, her “Squee!” now muffled by his shoulder, and by the third time he feels the tent re-assert itself.

_Oh god, she had to have felt that_ , and he can feel his stomach drop, a cold bead of terrified sweat running down the back of his neck. Mabel breaks off the hug, and Dipper panics, mentally racing to prepare what he can say to explain this.

_It’s all just a misunderstanding, I would never want to find you attractive. Er, I mean, you are pretty and all, but you’re my sister, and guys sometimes get weird boners, completely unrelated to seeing their sisters in swimsuits, honest, and ohwouldyoulookatthetime._

He runs through a dozen possible ways the conversation could end, most of them ending with her slapping him in disgust, or running off crying. In all honesty, he can’t tell which would be worse, but _anything_  would be better than the neutral expression she’s giving him now and-

Her little smile a moment later douses his internal panic, and after a blank moment he chuckles awkwardly before smiling back at her, grinning sincerely both at her enthusiasm as well as his own internal relief.

_She must not have felt anything!_  He can hear an internal hallelujah choir as he smiles and allows his shoulders to relax from the terrified tension they held a few seconds before.

Punching him in the shoulder, Mabel twirls and walks to the doorway. “Well, let’s get this show on the open road. We’ll need at least a half-day if we want to catch all the rides before the park closes, and this girl is a bonafied wannabe fish when it comes to water parks.” She crosses her eyes and purses her lips, making  _bloop_  noises as she imitates gills with her hands and runs down the stairs.

Dipper laughs, smiling as she leaves, and slips the keychain into his pocket before shrugging on a t-shirt before following her down the stairs and out the door. Soos gives him a thumbs-up from the waiting van as he starts the engine, honking the horn as Mabel waves him towards the car.

_Well, that could have gone a lot worse._


	2. Chapter 2

Soos lets out a whoop from behind the driver seat as they clamber into the back of the van. “Doods, good to see ya. Watermania, here we come!”

He had made the trip over here supposedly to see Watermania, the fabled “Week of Wet!”, but both twins knew that he would have found a reason besides half-off waterpark tickets to come visit. Dipper grins, sincerely, and seeing his toothy smile and the little ridiculously cute tuft of a peach fuzz goatee, Mabel can feel her stomach doing a bit of the butterfly dealio it was doing earlier.

She clambers in the back, sitting next to Dipper as he scoots a pile of Nyums and Candy Koalas the size of a small toddler off to one side, onto the pack of Pitt cola on the floor. “Hey, hey guys: Help yourselves!” Soos says, gesturing over the back of the seat to the small mountains of snacks. He grabs a Pitt for himself, cracking it open as the car pulls out of the drive and heads for the highway.

Although, thinking back, the feeling from seeing her brobro’s smile was definitely not as butterfly-y as the blot-out-the-sun butterfly-cannon she felt when Dipper poked her leg up in his bedroom. That was a bit of a shock; She’d had fun seeing the stares and, heh, physical reactions of the boys at the pool here in the hometown last summer, but Mabes definitely was not expecting her little brother to do that too. Judging from his looks of anxiety and relief, though, her smile didn’t give away that she’d  _definitely_ noticed his excitement.

On cue, the little voice of reason in her mind cropped up again. _It’s still a bad idea, you know. Dips won’t go for it, and you’ll just make stuff bleargh between you two._  She caught herself frowning internally, and nodding her head slightly, before the little mischievous voice in the back piped up.  _Well, Aiden never gave you jitters like that, and you made out with him! Mermando was the best thing short of a vampire and he didn’t even register more than a 2.5 on the Internal Butterfly Scale.  Heck, even the vampires didn’t come close to Dip._

She grinned and stared off into the middle distance, remembering vampiric boyfriends past but more largely revelling in the warm fuzzy feeling she’d gotten in the bedroom. Dipper leant in to be heard over Soos’ classic rock CD, saying with a smile “Hey Mabes, what’s so funny?”

She started and stifled a squeak of surprise, but turned to him a bit sheepishly and said “Oh, heh, it’s nothing Dippingdots. Just fun memories of the Mystery Shack an’ Grunkle Stan. Jus-just that, yupperski do.” He nodded, giving her an odd, slightly-sad smile, and then he leaned back in the battered seat.  _Good one Mabes. Remind him of the awesomesauce times at the Shack while we’re stuck here for the summer instead._

Mael sighed internally, and went to emulate her brother in leaning back, only to find a broken nub of plastic where the headrest would have gone. She frowned, trying and failing to comfortably situate her head on the back of the seat. Again, unbidden, a little grinning and innocently whistling part of the back of her mind said  _Well, I guess you can either sit upright and still the entire trip, use the case of soda on one side as a pillow, or use Dip’s squishy naptastic lap on the other side…_

Before the internal voices of reason could wake up enough to voice opposition to the idea, Mabel stretched out her arms over her head, yawning loudly. “Hey Dipper,” she says, pointedly poking the nub of warped plastic behind her head with a finger, “Can I start a napathon on your lap?”

The strangled, cracked reply of “ _Oh_ -Uh, sure? Sure, definitely,” is definitely making the part of her mind from earlier bounce up and down excitedly.  _Ha-ha, it wasn’t just nothing, was it! Of course,_ she thinks as the voices of reason get their act together,  _It also mighta just been some involuntary kinda thing, like when we see unpetted puppies that need petting._

The internal forum affirms this idea, more than a few stray thoughts veering towards the idea of adorable puppies as she lies her head down on Dipper’s lap. He hastily puts one of his hands down there, presumably to cradle her noggin but also probably making sure he doesn’t, well, get a stiffy and poke her again, this time in the back of her head.

 _Well, we could always turn to face the offending poker and see what we can do to stop the poking._ She feels the tips of her ears go crimson as heat flushes to her face and more than a little between her legs, while the rest of her mind interjects with  _Nopenopenope this is fine, this is more than fine, he’s our brother, just sit and relax. You’re already pushing it as it is._

Mabel began to take longer, deeper breaths as the CD and Soos’ off-key singing mixed with her breathing and the rumble of the road. Comfortable minutes pass, and soon the only feeling she was aware of was her brother’s warmth, and the rise and fall of his chest. After a few more relaxing minutes, she begins to notice that his breathing was getting shallower, faster. Mabel opened her eyes to see him peering down at her, an odd mixture of apprehension but also affection written across his face.

He notices her glance, and gives her a little awkward smile, that she returns. His free hand comes down and begins to rub the side of her bare shoulder. Butterflies beginning their thing again, she turns her head from being on it’s side until she’s facing directly up looking at him, and says “What’s got you smiling like that?”

He chuckles awkwardly, his other hand going to rub his neck as he glances out the window before looking back down at her. “Oh, heh, just, you know, trying to sort out some thoughts and stuff. Nothing important, don’t worry.” She feels a twinge of sadness at the last part, until she sees that his face is displaying the exact opposite, his brow doing the little funny birthmark-squishing thing it does when he’s deep in thought about something important.

She reaches a hand up to his cheek, causing him to start at her touch and feeling a distinct throb from the hand under her head. As he looks down at her, Mabel gives him a broad smile and begins to say “Dip, I-”

Just then, the van swerved to one side, and hit a massive pothole, sending Mabel’s head up and slamming back down right onto Dipper’s crotch. He let out a  _“Hrgmph!”_  and a low under-the-breath keening noise of pain as Mabel abruptly sits up, saying “Oohsorrysorrysorry” and hugging Dippingsauce around his shoulders.

Soos calls back “Whoa, sorry guys! Dey really got some impressive potholes over here,” apparently oblivious to Dipper’s plight.  _Well, it’s not like I can exactly kiss it and make it better,_  she thinks as she continues to hug her grimacing brother, although the thought of that does send a little spark of flush to her cheeks and between her legs. She brushes off the thoughts, and as they slow down, they cross a pair of speedbumps, each eliciting a strangled “Eep!” from Dipper.

“Hey, hey, hey, check it out doods-Watermania!” Dipper was still distracted and leaning forward, eyes watering and continuing to make quiet unhappy noises, but Mabel was able to look out the window to see the waterslide-topped magnificence with her own eyes.She squinted, but couldn’t quite see the ride she was looking for.

As they pulled into a parking spot, she helped Dipper limp his way out of the car. “Ah man, what the heck happened to you?” Soos said before her brother’s wheezing and groaning clued him in. “Oh jeez, that sucks man. Hey, hey, you want me to go and get you like a snowcone or something?”

Dipper let out a noncommittal shrug, and Soos gave him a look of sympathy, before getting in line to get their tickets. “All right man, but you let me know the second there’s anything I can getcha to help.” Dipper gave him a weak smile, before groaning after taking a few more steps.

As she walked forward through the gate, while most of her attention was focused on helping support her injured brother, part of her was simply crossing her fingers in the hopes that there wouldn’t be any more problems with her hopes and plans for today.

_Oh man, please let it be open, please let it be open._


	3. Chapter 3

Walking was pain, standing was pain, existence was pain. Sitting was less pain, until Dipper needed to shift a leg, at which point it quickly shot back up the list to be a top pain contender. The pain was less than it had been when they were in the parking lot, bearable now and not life-ending, but he certainly was starting to wish he’d stayed home where all the icepacks were and potholes weren’t.

Still, Mabel’s suggestion of “cooling off” in the colder wave pool was a good idea, and after he’d popped briefly into a restroom to make sure nothing looked irreparably damaged, he joined them out in the shallows, wincing as the first wave it but then sighing as the cool water soothed the pain.

He also finally had a chance to appreciate her swimsuit as he waded into the water: It was a new one, a deep cherry red, with a simple front but a strappy back and a little enameled metal cherry charm dangling from one of the bikini strings. Little blue-glitter cherries adorned all the non-strap bits of fabric, shimmering in the water and noon sunlight. He could hear her laughter before he could even see her, and seeing her was like watching a mermaid as she splashed and swam around, letting out an excited “Dippingdots!” before diving to surface next to him.

He tried not to stare below her neck, as he didn’t want to flare up the pain, but he felt a stab of hot annoyance and anger as he saw the gazes of a few other guys in the wave pool looking over his sister as she swam by.

 _Wait, anger?,_  part of him reflected.  _You were never angry at her boyfriends, so why would you be mad at some strangers?_

 _Weeelll, that’s not exactly true,_ part of his memory chimed in.  _You did kinda detest Aiden. And Justin. Heck, even Mermando, and that was a one-time fling._ He sighed internally, coming up with mental justifications that he just as quickly shot down. One solid point remained standing after a few minutes of cooling off and reflecting:  _You want Mabel to be happy, and she’s never been happy, really happy, with anyone but, well, you._

They splashed around there for a minute as Dipper waded deep in thought, before the majority of the throbbing subsisted. After giving him a questioning look and getting a painless and enthusiastic nod in return, Dipper followed Mabel to the first of the rides of the day. Given that it was used briefly and for medicinal purposes, he hadn’t checked off the wave pool on his mental list of rides yet, and filed it instead in the ‘Incomplete’ folder; If they were going to come to a waterpark, he wanted to make sure they were going to do it right and hit every one, since it might be another year, or more, before they could come back again.

“The Mountain” was a simple ride, and was little more than just a series of slides; Nothing fancy, with a trio of different slides of different complexity, interweaving like a drunken braid before ejecting near the bottom of the pool. The line was fairly short for this one, and within a few minutes of standing around on too-hot cement and trying not to stand with his thighs together, he and his sister were standing at the entrance for the ‘Black Diamond” slide.

Mabel was about to go sliding in first, when Dipper had a horrible thought of her getting stuck or slowing down, and him ramming her head back on the freshly-tender injury. “Uh, how-howsabout I go first, huh Mabes?”

She looked at him confused for a solid fifteen seconds, and then glanced down before quickly glancing back up, her face filling with understanding. “Oh. Ohhh. Definitely!” She took a step back, and made a royal bow gesturing him towards the rushing entrance of the slide.

Dipper gave her a thumbs up, which she returned with finger pistols. He took the opportunity to feign death at her finger-pistol assault, collapsing into the tube with his arms crossed and nearly losing his balance in the process. He slid down the tube and his world became a blue blur. There was the swish of water to left, right, and left again, sending him at one point uncomfortably close to the raised lip of the slide, before after a few more seconds he was spat out into the waiting pool.

He had barely managed to slow down and get his feet on the landing pool floor, when he hears _“Cowabunga!”_ from behind him. Before he can dodge, Mabel comes scooting out of the tube, almost skipping across the water like a stone, and thumping into the back of her neck. He grins for a moment, and she gives him the command “Up!” like an imperious camel driver.

He strained, for a moment or two; He’s been working out, but genetics dealt him a hand of blown raspberries when it came to strength, and even actively working to try and build muscles beyond his old noodle arms was  _almost_ entirely futile.

Almost, but some degree of that work paid off, and he lifts her into the air with a whoop from them both, eliciting bemused smiles from nearby park-goers. Soos waves at them from a nearby corn dog stand, and Dipper begins walking towards him, still piggybacking Mabel. The feeling of her soft thighs against the side of his heads suddenly has those thoughts bubbling back up from earlier, and then the realization of her bikini-clad mound directly behind his head had him breathing shallowly and his vision starting to spin pleasantly.

Then there was a stab of familiar pain as the injured dick tried to reawaken, and he stopped short, groaning in pain and his shoulders giving a momentary shake as Mabel asked “Whoa, Dippers, what’s wrong? You ok down there?”

He groaned again, quieter this time, but she quickly dismounted, in the process sliding her chest against his bare back for an agonizing second. The stiffening pain throbs again, and he hobbles over to a rock to sit down as Mabel follows behind, repeatedly asking him what’s wrong.

He gives her a weak shrug and equally weak smile. “Oh, nothing. Don’t worry about it.”

Mabel immediately dismisses his feeble attempt at misdirection with a narrowing of her eyes. She sees him double over as the pain surges one last time before receding as he begins to soften, and as he watches her eyes go from confusion to surprise, and- _Is she blushing? Oh shit, she’s totally blushing._

His sister began to flush across her ears and face; It’s faint compared to the pink toasty sheen the sun has provided so far, but he can see it, and he breaks eye contact before she can say anything. She gives a single awkward chuckle, and says “Well, erm, hokay. I, uh, I guess I’ll wait over here until you’re ready to, to tally-ho to the next ride.”

She sits over at a nearby bench, still watching him with concern in her eyes, and after another minute or two of rest Dipper regains his breath and stands up, taking a few experimental steps. The pain has mostly abated, and while there’s still a minor twinge, it’s better than it even was immediately after the wave pool. Mabel gives him a look, which he can’t tell is more anxious or worried, and he gives her a thumbs-up and a grin.

She breaks into a broad smile, and comes over next to him as they wander down the path. “Man, you’re like the energizer bunny: You just keep going.” Dipper grins, but before he can stop it an evil bubble forms and hijacks his mouth, saying “Oh, you haven’t seen  _anything_  yet.”

He stops in his tracks, going slightly cross-eyed as his noble-monkey-brain catches up to what his debased-lizard-brain made his completely-impartial-mouth say. Mabel has stopped as well, making a single noise that the can’t tell whether it’s a squeak from her shoes or her mouth. His bile begins to rise in his throat as he worries that she’s about to call him disgusting and run away from her dirty-minded twin, but she just says “Uh…huh,” like she’s puzzling over a particularly difficult knitting pattern rather than what just spilled out of his mouth.

After a tense few moments, she looks up at him, her face still slightly flushed but giving him a toothy smile. “Well, ready to try the Whitewater Terror?” He smiles back, letting out an unconsciously-held breath, and before he can reply Soos comes running up.

“Ah, doods, doods, check it  _out!_ ” He shows them a pair of little cheap water pistols, with a huge “WEEK OF WET!” logo emblazoned across the water tanks. Before they can say anything, he shoves them into Mabel and Dipper’s hands, saying “Here doods, take ‘em as like souvenirs or somethin’. I got lotsa tickets, heh, so it’s like no big deal.”

The twins accept the gifts with a smile, as Soos looks back up towards the arcade area before looking back to them. One of his pockets overflows with tickets from the arcade, and he says “Alright doods, I’ll catch up with you in a minute. Melody loves teddy bears, and there’s a talking Bear-O doll she’d probably  _love!_  Catch you later!”

Before he can say “Wait, Soos, I’m not sure that’s a good-” Soos is out of earshot, running towards the arcade. Dipper sighs, and smiles as Mabel shrugs and says “Well, hey; Maybe after getting to see Bear-O come to life at Hoo-Ha’s, she might want a talking version of her own?”

They maintain eye contact for a long moment, before they can’t keep a straight face any longer and both begin to laugh. They begin walking towards the next ride, and his sister hands him her water pistol, both of which he shoves into his surprisingly-spacious trunk pockets.

As they walk, his hand brushes Mabel’s, and she takes Dipper’s hand, sending a surge of warm goosebumps up his arm that he hopes she doesn’t notice. It’s nothing they haven’t done as twins before, but for some reason this time it’s making him feel, to use a Mabelized term, “fluttery,” in a really, really nice way.

_Maybe, just maybe…she might feel the same way?_


	4. Chapter 4

Mabel and Dipper both groan as soon as the line comes into sight. Whitewater Terror’s line wraps almost fully around the ride itself, but Mabel hasn’t come this far just to give up now.

 _Besides,_  she thinks,  _Dip would probably start getting his suspicion-brain all suspiciony if we skipped one, especially this one._ He’d brought up this ride every time the Watermania trip came up, and she knew if they skipped this one he’d be dejected for the rest of the trip.

_And that certainly won’t do for later. At least, assuming everything keeps going hunky-dory along with my surefire plan._

The twins walk to the back of the line, behind a trio of giggling college girls who are busy apparently ranting about a mutual annoying friend. Mabel abruptly feels a tinge of embarrassment and anxiety; Their swimsuits are filled out much more than hers while being simultaneously smaller, and she begins to regret her choice of attire.

The Cherry Bomb was cute, but there had been those two canary-yellow and teal pieces that had been much smaller and risque than this one, but she had dismissed them because of the distinct lack of glitter and…well,  _fun_ , for lack of a better word. They didn’t feel Mabel-y, but she began to chew her lip as she wondered if maybe Mabel-y shouldn’t have been her biggest priority for what to wear.

Dippingsauce must have noticed her anxiousness, since he abruptly stops the eye-roll he was making towards the girl’s conversation. He looks at her, concern radiating from his eyes, and she is suddenly lost. Looking over the wide eyes, she could make out the slight wrinkles around the edges from experiences no kids should have experienced, ones that probably aged them both by years. Dipper always had protected her, and the hint of sadness his expression held always reminded her that her brother always was the one to take the brunt of whatever baddies or monsters or mind-blasting terrors life had thrown at them. She can’t help but smile as she sees the eyes crinkle in a smile with his words, as he-

Wait, words? Oh crap; She’d kinda-sorta-maybe been not paying attention, and so had to stumble out a “Oh, uh, what? Sorry Dippingdots, I was kinda lost in thought there for a sec.”

He chuckles, warmly and with a surprising degree of understanding she doesn’t always hear from his voice. “Well, for one, we’re about to lose our spot in line.”

He gestures up at the large gap between them and the college girls, and Mabel grabs his hand again, yanking them forward to make up the distance as he lets out a “Whoa!” in surprise. They come to an abrupt stop, and again the swimsuit-clad older girls have Mabel chewing her lip.  _If I wanted to catch Dip’s eye, I definitely should have brought my A-game. Ergh, Mabes, ya done goofed and-_

A gentle hand on her shoulder turns her to face her brother, a soft smile on his face as he looks at her in concern. “Mabes, what’s wrong?”

She gives him a wide grin. “Wrong? What, the Mabester? Nah, nuthin’s wrong little bro, your Alpha twin is A-ok right now-”

Her voice cuts off as he gives her a look of disbelief, and she shrugs, wishing desperately for one of her sweaters to retreat to. “Come on Mabel, you’re doing your lip-bite thing. What’s up?”

She can’t help but glance towards the trio of giggling girls in line in front of them, and Dipper follows her gaze. He looks confused, but then his gaze drops to see where she has unconsciously shifted her arms to cover her own comparatively-flatter chest. His mouth forms a little ‘o’ of understanding, and he takes a step forward to hug her, her head against his shoulder.

Her eyes begin to well up, even as her little internal voice says  _Stupid tears bein’ stupid for no reason. Dip’s free to look at whoever he wants, and it was a dumb idea to even try and Cherry Bomb it up today._ She lets out a little quiet sob, shaking once, and while nobody else probably heard (The two guys behind them are too busy arguing about which ride was the best), Dipper lets out a quiet “Oh man, Mabel, it’s ok, it’s ok. Shhhh, it’s alright, I’m here.”

She sniffles and takes a shuddering breath even as his soothing voice calms her down, but still her thoughts keep cropping back up and reminding her that this was a bad idea all-around. _You woulda had just as much fun in the Captain Elephant shirt and wouldn’t have had to be all weird and cry about some girls who never did a thing to you._

As the next few minutes pass, the line shifts forward a few times as she moves to standing next to Dip. Her brother just guides her forward, his hand laced with hers and her eyes still squelched shut so she doesn’t have to see him obviously staring at the girls in front, with their tight butts and their put-the-Mabel-brand-sweater-puppies-to-shame breasts.

But when her eyes open, Dipper is just looking at her, quiet concern still written all over his face as he tries to keep a weak smile going. “Mabes, don’t compare yourself to them. You look amazing,” as her heart does a little fluttery thing that tickles her back of her throat as well as sends a little warming tingle all over her, “And I’d bet that any guy here thinks you look amazing as well. Alright?”

He finishes that last sentence tucking a finger under her chin to lift her head so she meets his gaze, and gives her a smile that makes her chest do the flutter-thing again. She returns his smile, saying weakly “Heh, yeah, ‘any guy.’ If you say so brobro.”

 _But I don’t care about ‘any guy,’ I care about ONE guy, and that guy isn’t a guy who should be thinking I look like that._  A little thought pipes up:  _Well, fuggedabout “should,” he’s the one who DID say we look amazing. That’s gotta count, right?_

He gives her another smile, his hand giving hers a squeeze. “I know so. Trust me, I call ‘em as I see ‘em.” She grins, and she feels a flood of heat to her cheeks as she realizes that his face- _His amazingly kissable and smoochable face_  the little voice interjects-is just a couple inches from hers.

Almost unconsciously, she starts to lean forward, all sorts of alarms and internal thoughts saying  _This is a bad idea Mabes, knock it off before you embarrass yourself and have to go live in a cave in the woods with Waddles for shame._

And then, her heart skips at least three beats as she feels him lean back towards her.

_Yesyesyeswheeeeeee-_

“GAH!” Dipper stars backwards from her, and for a moment Mabel’s world begins to shatter around the edges.  _Bad idea, bad Mabel, the plan was never gonna work and now everything is all gunked up and Dip’s gonna hate you forever,_ she thought as she opens her eyes to see Dipper staring behind them.

She glances that way, and suddenly feels the warm, happy flush become a burning of embarrassment as she sees the two guys behind them, staring at her and Dipper. She involuntarily lets out a squeal and takes a sharp step backwards from Dipper, bumping her shoulder hard against the metal rail fence alongside the ride perimeter.

She barely notices the bump, and the two guys who had been watching them cough in embarrassment as Dipper glares them down, letting out a “Oh, uh, sorry,” before shuffling to look the other direction. Mabel was feeling quite sure that if they’d still had the Journals, he would have cursed the guy on the spot.

As it was, though, silent glaring apparently did the trick. After a couple of seconds of mortified silence, one of them nudges his friend off in the direction of the rest of the park, and they leave with a second, muttered but sincere “Sorry.” A mom and three squealing children replace them, but by this time Mabel is staring rigidly straight ahead, her thoughts a jumble as she starts to hyperventilate.

Her breath catches as she feels Dipper’s hand grab hers, interlacing fingers again and giving hers a squeeze. She looks over to him, and behind the identical blush of embarrassment and sheepishness of his smile is a look of, dare she think it, hope?

 _Oh man, oh man, it totally is!_  That look seals it, and she returns his smile and hand-squeeze, and his smile breaks into a toothy grin and awkward laugh. She joins in the laugh, and it goes from awkward to wholehearted as she feels tension melt off her shoulders, not just from the interruption but tension from, gosh, days and weeks and months of thought and worry about this trip.

She enjoys the warmth of his arm as they stand shoulder to shoulder, and is surprised to see them pass the churro cart they saw before getting in line, the one that was right close to the head of the ride. She points it out to Dipper, and he tells her “Hang on a sec,” before ducking under the handrail and going to the cart.

She giggles with excitement as he comes back with two warm, drowning-in-sugar churros that they munch while waiting the last few minutes of the line. While the sugar was a nice pick-me-up for her mood, better still is her arm and the comfort of holding his hand, where he occasionally gives her the light squeeze and sends thrills across her.

They finally reach the top, where a bored lifeguard says something indistinct to the girls ahead of them and they file into one of the huge rafts. This was one of the new rides, one Mabel hadn’t been on before, and it had a big six-person raft that everyone sat on and held straps as it plunged through the corners. Already sitting there was one bored-looking elementary-aged boy wearing a t-shirt and a sour expression; Mabel guessed the rest of his group got to ride ahead or something.

As they came up, the lifeguard glanced over them before looking at the raft, saying “Alright bud, you can sit over there on that side, and your girlfriend can sit over there to balance it all out.”

She can feel Dipper’s hand tense before he lets go, trying to stammer out a “Uh, b-but she’s, well, she’s not actually-uh, heh.” The lifeguard just rolls her eyes and says “Whatever” in a flat tone, pointing Dippingsauce to the other end of the raft. Mabel takes her spot, one of the college girls on either side, as she loops her arms through the provided straps.

She has another moment of fleeting anxiety, seeing the girls next to her compared to her own body, but looking up her brother’s gaze is giving her and her alone a warm smile as the raft gently sets off. She feels a bit of heat race down her as he looks her over appreciatively, and can’t resist a slight giggle as she sees him starting to sport a bulge in his shorts again.

He notices her giggle, raising an eyebrow questioningly, to which she just looks down at his crotch and back to his face. He follows her glance, and she can see him blush and look away in embarrassment with a quiet little “Erk!” Mabel laughs, and laughs again as they all scream in excitement as they go over the first drop.

A splashy and spinning minute later, the raft has been ejected into a little lazy river, and the other occupants begin to file out. One of the girls is raving to go again, but her two friends point back off towards the wave pool, while Annoyed T-Shirt Boy, as Mabel dubbed him in her head, has run off to catch up with a group of other kids around the corner.

She accepts Dipper’s gentlemanly hand to help her out of the raft. “Well thank you Sir Dippingsauce. Your kindness shall not be forgotten,” she says, as she begins walking in front of him down the cement path.

She freezes, though, when she hears him say “Oh god, Mabel!” in a voice etched with distress.

Unbidden, the little voice of pessimism returns: _It was too good to be true. You probably doinked everything up and it just took him a minute to realize it._


	5. Chapter 5

Dipper’s face was ashen, his breath coming in short bursts as he saw Mabel, a mantra in his head repeating  _Oh no, oh no, oh god, oh god._ Her expression was that of puzzlement, and then a slightly-open mouth and wide eyes revealing a deep emotional hurt rather than the twisted-up expression she made when something physically hurt.

He was not expecting  _that_ face, but he couldn’t help but stare at her blood-covered shoulder. Mabel noticed the direction of Dipper’s stare, and as a lifeguard came running up saying “Hey miss, you need to come over to the first aid station,” she saw that her upper shoulder was a mass of red.

Dipper could see her purse her lips and reach back to poke her shoulder, and when a few tentative pokes produced nothing more than a minor wince, he forced himself to relax.  _It’s just a flesh wound, not a life-threatening thing._

The lifeguard also looked relieved at Mabel’s calmness and obvious lack of pain, and in a voice lacking the worried urgency from a minute ago, points them towards a squat, white building trimmed in red. “Just head on over there and Avery can get you some stuff to clean that up. Don’t worry about it; The water usually makes injuries look worse than they really are.”

Mabel nods, and Dipper thanks the lifeguard and takes her hand as they walk over towards the building. He can feel her arm and gait is stiff, worried, and he remembers the way she looked at him when he’d first noticed her shoulder.

Her voice breaks the awkward silence. “Musta banged up my dumb shoulder on the dumb guardrail earlier. Sorry for being a bleedy mess right now,” her tone dropping as she continues to stare at the pavement. Raising her hand up, Dipper kisses her on the back of her hand, and she looks up at him, smiling warmly as he can feel her relax alongside him.

Then his sister begins convulsing in giggles, stopping for a second as she tries fruitlessly to cover her giggling mouth with her hand before they squeak out the side into a belly laugh. Dipper smiles, confused but glad to hear her happier than he’s heard her in months. She hasn’t been sad, per se, but her excitement most months seems muted compared to those amazing summers in Gravity Falls.

She holds up her hand by way of explanation, and Dipper’s eyes widen as he can see that more than a little of the watered-down blood from her shoulder has covered her hand. “Uh, not trying to crimp your style Dippinsauce, but-” she breaks into a fit of giggles, “-But I think I might have some lipsticks you should use before you jump all the way to Blood Red.”

Dipper blushes in embarrassment, chuckling as he wipes off his lips with the back of his hand. The worker at the first aid station, a beaming brunette lady who looks about the same age as the twins’ mom, comes bustling over to the counter near them. She notices Mabel’s injury straightaway, and tutting she gives her a mock finger-waggle.

“Did someone sneak into a ride that was too big for them?” she scolds lightheartedly, the lanky teens going along with the joke and shrugging apologetically. Avery, as her nametag confirms, begins scuttling between a few drawers, and after a few minutes presents them with a bandage, some sterile gauze, and a bottle of rubbing alcohol.

Mabel’s cheeriness takes an abrupt dip, and she lets out a forced solitary laugh as she looks at the bottle of alcohol. Her voice says with a hint of a waver, “Hey now, I don’t think it was quite that bad. I mean, hey, what are water fountains and soap for, eh?”

Avery, to her credit, gives Mabel a look of sympathy, but says reluctantly “Normally, yes, but there’s enough people going in and out here that there’s all manner of nastiness that could bring you down with an infection, even with the chlorination.” Dipper grabs the bottle, and gives his sister a reluctant smile.

“Well, unfortunately I think I have to agree with the lady Mabel. I can at least help get you cleaned up, though,” he says, putting a bit of lightness into the end. Mabel still looks reluctant and somewhat scared at the thought of the pain, but nods.

Avery points them towards a back area of the aid station, essentially an open porch with a couple sets of padded benches and privacy curtains hanging to keep bugs and prying eyes out. Dipper and Mabel both thank Avery, and head back there. The only other person in the porch area is a young child, judging from the sniffling cries, but as Dipper holds a curtain open for Mabel to enter, they can hear a parent saying “All right now Henry, let’s get going home. You want ice cream on the way back?”

The sounds of the now-excited child fade, leaving Dipper and his sister alone on the covered porch with only the background buzz of conversation and splash of the rides in the distance. He begins opening the bottle of antiseptic, when Mabel puts her hand on his arm to stop him.

“Shut your eyes,” she says breathily, and Dipper can feel his heart hammering against his chest as trills of electricity begin racing down to his shorts and across his bare chest, where the gentle breeze is teasing his few-but-proud chest hairs and drying the water leftovers from the last ride.

He does as she asks, and can feel her get up, and take a step towards him. His heart is pounding in his ears as she stands on tip-toes, right in front of him and-

Wipes something across his forehead?

He peeks open an eye as she begins quietly singing the opening lines of The Lion King, and then opens and rolls his eyes, sighing heavily as he realizes what she’s done. Mabel breaks down into a fit of giggles as she steps back, and says “Sorry brobro; I wanted to make sure I took advantage of the opportunity before I got cleaned up..”

He groans, but smiles back at her and licks a thumb to wipe off the smear of symbolic blood on his forehead. He turned his attention back to the bottle of rubbing alcohol when Mabel took a step forward again. He nearly dropped the bottle in shock, looking up to meet her gaze. Her warm eyes were melting, enveloping, and he smiles. He’s trying to think of what to say when-

She leans forward, and kisses him.

Dipper can feel his body respond, the heartbeat in his ears returning to form a raging white noise that drowned out all sounds of water and conversations and anything else in the park that wasn’t his abruptly-ragged breathing, Mabel’s warm breaths on his chin as she breaks the kiss, the breaths sending a flush all the way down his chest, and the quiet rush of wind that was rustling the curtains and giving him goosebumps, and doing the same to Mabel judging from the little shiver she gave.

She looks at him, and he can see some of the concern and anxiousness that he saw earlier, but that melts away into excited eagerness when she sees the corners of his eyes crinkle in a smile. He reaches to pull her into a second kiss, this time savoring her flavor, the vanilla-bean glitter lipgloss, the warm taste of her mouth as her tongue darts out to run along his lips and plunge  into his. She lets out a little muffled happy noise, partway between a moan and a happy sigh, and he can feel himself give a similar noise in return.

He pulls her close, and begins to run his hands over his sister’s shoulders. She shivers at his touch, but then begins to run one hand through his messy hair as the other feels along his back, digging in slightly with her nails as he cups her ass and pulls her towards him.

He can feel himself stiffen, but with a mischievous grin he pulls her close this time. Mabel notices his expression, and breaks off the kiss to start to say “Dip, what’s so-” before he hugs her close to him, his cock straining against the thin material of his shorts as her eyes widen. A second later she lets out a little appreciative “mmm” as her hand reaches down from his back to cup him and feel his hardness through the suddenly-inconvenient trunks.

He groans, and leans down to kiss between her warm breasts, running kisses up and down from her neck to her sternum and feeling himself get even more excited as he hears her breaths become faster and shorter. Dipper shifts aside some of the crimson, sparkly material covering one of her breasts, revealing a little pink areola with an erect nipple, goosebumps ringing all around it.

However, before he can do anything more than lean forwards in preparation for a kiss on the revealed breast, the sounds of the aid station door opening interrupts him, causing him to jerk back. Mabel hurriedly lets him go, frantically rearranging the swimsuit as she and Dipper both take deep breaths so they don’t sound like they just ran a marathon. Their faces flush, Mabel gives him a cheeky grin, but her eyes widen and she goes stiff when Avery’s outline can be seen against the white curtain.

“You kids coming along ok in there?” she calls, and Dipper lets out a little sigh. Mabel replies, saying “Yup, we’re doing great. Almost done over here, and we’ll bring over the alcohol and leftover bandages once I’m set!”

Avery replies with just a simple “Okiedokie then! I’ll be right over there if you need me!” before her outline fades and the aid station door can be heard again. The twins make eye contact, and begin giggling quietly at their narrow escape.

After they catch their breath, though, Mabel gives the alcohol bottle a long look before looking to Dipper. He nods solemnly, and takes a deep breath to brace himself as he douses some of the alcohol onto a gauze pad. He can feel her shoulder tense, and he begins dabbing the set of small cuts with the end.

She hisses through her teeth, before letting out a gritted “Ow. Well, that wasn’t so bad after _HOTBELGIANWAFFLES THAT STINGS, THAT STINGS A LOT! OW. OW OWOWOW.”_   under her breath. Dipper tenses in sympathy with her as her shoulder shakes, and he murmurs “Oh god I’m sorry Mabel. I’ve almost got it, I think, just one more spot,” as he hurries to get another soaked pad ready. She tenses again, and this time says nothing, and instead hisses again through her teeth before letting out a little “ _Eeep_ -ergh-errrgh,” letting out a shaky breath as the pain fades.

Dipper gets a bandage stuck over the cuts, patting it gently, but putting a hand on her shoulder as she goes to get up. “Uh, Mabes, you still look like a murder victim. Gimme a sec to wash all that off,” he says as he bundles up the extra bandages and alcohol and steps out to the aid station.

Avery gives him a questioning smile, and he just sets the supplies back on the counter, saying “I think this will do the trick. Is there a water fountain or something I can use to get the rest of the blood washed up?”

She nods. “Yup, right over there behind the curtain area is a little washup sink. Should do the trick?” Dipper nods, and thanks her again before walking over to the sink. He couldn’t help but notice that she was decidedly less chatty than when she was first helping them, and his cheeks began to burn as he realized she might have realized what they were doing.  _Calm down Dip, calm down. Take a breath; You’ve never seen her before, you’ll probably never see her again, and for all she knows, you’re just a boyfriend and girlfriend and nothing more._

He took a long breath to calm himself, and a little part of him noted excitedly that the idea of Mabel being his girlfriend sent a warmth to his core, one that he couldn’t even remember having when he and Pacifica or Candy were dating. Calling out “One sec, Mabes,” he crossed around the curtains to the sink.

Well, “sink” was a stretch. It was actually just a sturdy plastic bucket with holes drilled through the bottom, and bolted to a post with a faucet head sticking out the top. Still, the faucet water served his needs, and he wet a stack of fresh gauze before coming back in to help Mabel.

He nearly dropped the gauze: His sister was standing, but her bikini top was unlaced and laying on the bench. She dropped her arm from her chest shyly as he carefully put the curtain back into place, and he could hear her say in a quiet murmur “Well, I thought this might be a bit easier to clean up, so there’s not a bunch of complicated strappy doodads to work around?”

She was trying to keep it lighthearted, but Dipper could hear the uncertainty in her voice. He nodded, murmuring a choked “Yeah, that’ll-that’ll work great,” as he struggled to keep coherent thoughts.

He stood next to her, and she turned, showing her bloodstained back to him. He began to work carefully, rubbing with the cold water and making her shiver, but cleaning all traces of blood from her shoulder, back, and arm, careful to avoid the fresh bandages. She shuddered again, letting out a little happy noise as he ran his empty hand along her arm, gently grabbing her delicate wrist before lifting her hand back so her could give it a trio of little kisses, making her giggle.

He ran his hands back down, leaning forward so his breath was along the nape of her neck; She shuddered, moaning quietly as he began tracing up her stomach and chest, cupping her breasts and giving them a light squeeze. At that, she turned her head and caught his mouth in hers, kissing him deeply, passionately, muffling her groans of pleasure against him as his hands continued to explore her.

He could feel her knees start to go weak as his hands began travelling back down again, running past her stomach, down her side to run along her hips, and then back inwards and up her thigh. He had nearly reached the base of the cherry fabric when the sounds of a crying little girl cut through their pleasant reverie, and Dipper couldn’t help but groan, Mabel echoing his disappointment as they broke apart.

He could hear Avery say “My, what a big splinter for such a little girl! We’d better get that looked at right away!” as Mabel put her top back on, and he bundled the soaked gauze and tossed them into a little wastebin before stepping out of the curtain, followed a second later by his sister.

Outside was a disheveled-looking older man, evidently the father of the little girl, who was wearing a fluorescent-pink polka-dot swimsuit, water wings, and was holding one hand like the bones in it were shattered. Dipper could see a tiny brown fleck on one of the fingers, and gave her a sympathetic smile. He was about to move on when Mabel’s hand stopped him.

In a murmur, she said “Hey Dip, looks like someone could use a pick-me-up. Do you suppose Soos would be overly upset if we donated one of those water pistols he gave us?”

Dipper shrugged, and retrieved the one from his right pocket. He handed it over to Mabel, who went to go give it to the little girl, saying “Well, that looks like a mighty nasty wound there little lady!” as she crouched down to look the little girl in the eye. The girl nodded solemnly, tears visible in her eyes, but Mabel, with an air of formality, presented her the water pistol. “Well, only the bravest of Water Warriors can wield a weapon such as this. Do you think you’re up for the task?”

The little girl let out a “YES!” and little squeal of excitement as she grabbed the gun, and Dipper could see the girl’s father smile in relief. The father reminded the little girl “Now what do we say?”, resulting in her nearly tackling Mabel in a hug with a little squeaky “Thank you sparkle lady!” before she followed her dad and Avery towards one of the curtained areas.

Mabel stood up, a wistful look in her eyes, before her brow furrowed in mock concentration as she said “Hmm, Sparkle Lady. Y’know Dip, that might be the next official title of Lady Mabelton if she ever gives up her throne.”

They both laughed, and Dipper gently grabbed her hand, giving it a loving rub with his thumb as they walked. However, he felt a sinking feeling as he stuck his hand in his pocket, feeling something soggy and lumpy in the pocket under where the pistol had been stowed.

_Oh no. Oh nonono._


	6. Chapter 6

Mabel dealt with the news well, at first. Dipper’s shaken and apologetic expression informed her that something very-not-good was in his clenched fist. Even then, when he revealed the wet, misshappen and smeared paper journal, she could feel the back of her throat clench as her vision suddenly blurred around the edges.

It wasn’t like the journal itself was hard to make, and she had whipped it up in just a few hours when she’d been crafting it for him, but seeing it ruined and pulped was like losing a part of their memories in Gravity Falls. That little journal hadn’t seen the outside of the trunks for years, but the real journal… _Oh man, that was the one that started it all._  All the good, all the bad, and probably quite a bit of what happened in between, and the representation of those unforgettable moments was sitting soggy and forlorn in Dipper’s palm.

She took a shaky breath, willing the tears down, but every instinct was pushing her to find a quiet corner to sit down in and hide in Sweatertown. Dipper pulled her into a hug, murmuring “Oh god, I’m sorry Mabes, I’m sorry. I totally fucking forgot I had it in there when we went through the slide. I’m-I’m…sorry, Mabel. I’m sorry.”

He repeated that over and over, kissing her forehead repeatedly and gingerly holding the back of her head. His touch and soothing words wedged open the cracks, and Super-Composed-Mabel Dam broke open, and her shoulder began wracking sobs.

He gently guided her over to a bench, where they sat and she leaned forward into the nape of his neck, still crying with her shoulders shaking as he held her close and made soothing noises.

_Ugh, it’s so STUPID; Mabester, this is an awesome day, so why’re ya dorking it up with the cry-fest?_

But she couldn’t help it; Weeks of apprehension were coming loose, the tension and uncertainty and fear unwinding in the certainty of his caring embrace, but they mingled with the worries and setbacks they’d already had today, along with whispered thoughts that she had stamped down and ignored earlier, but now wormed their way to the surface and took the lead, stamping down her other conflicting thoughts and repeating:  _It’s too good to last._

 _Eventually, maybe today, maybe in a week, maybe in a month or a year, but eventually he’ll realize this is bleargh to do with his twin, his sister, and then not only will you have lost this,_  and her mind filled with cold echoed reminders of the warm tittters she felt as he held her, of her heart racing as he gingerly kissed her in a lovey-love-you way rather than a you’re-just-my-sister way,  _but you’ll lose Dipper as well. He’ll probably hate you forever, and that’s assuming he doesn’t come clean to your friends, the school, or Mom and Dad._

After a few minutes, wracking sobs had gradually lessened and came out as little sad “mews” as she continued to rock back and forth, her legs tucked up to her chest. Dipper’s comforting arm was wrapped around her, his head nestled against her still-wet hair, and as he noticed her calming down, he ran a hand down the side of her face, tracing her jawbone to the edge of her beglittered lips.

“Hey there sad kitty,” he said with a sympathetic sad smile, and she managed a weak smile in return, punctuated with another sad “mew.” He leaned forward, and gave her a brief kiss on the lips, touching for just long enough that she could taste him, but pulling away right before she could do more than that.

An hour ago she would have been over the moon after him doing something like that, but that was before her dumb brain had to go and remind her of why this was a bad doomed-to-fail plan all along. She frowned, biting her lip and looking towards the tips of the distant trees beyond the park as she tried and failed to cheer herself up with thoughts of Smile Dip, puppies, glitter. Even her last resort thought, that of puppies carrying glitter-infused Smile Dip like mountain rescue dogs carried whisky flasks, failed to alleviate or even distract her from her anxiety.

She looked back to Dip, and the compassion and concern in his eyes made her heart begin to race happily and twinger the edges of her mouth upwards in a small smile, before being tamped back down as the familiar and unwanted thought of _It won’t last forever_  echoed in her mind again. He noticed the smile fade as she broke his gaze, and held her hand as he brushed a long, damp brown curl out of her face. “Mabel, what’s wrong?”

Her shoulders shook involuntarily, betraying the false choked optimism in her stilted reply. “N-nothing, Dippingdots. Just,  _heh_ , ah, just havin’ some thoughts. Dontcha-dontcha worry about it, alright?” She gave him a forced smile that lasted for only a second as her own turmoil resurged, sparked by the look he gave her as she could see the tears shimmering at the edges of his eyes too.

He hugged her close, his grip firm, but she could hear his voice crack as he murmured to her “Mabes, I’m here. I’m here. Everything’s going to be ok, it’ll be ok. Tell me what’s wrong, and I can fix it. I love you, and you can always tell me anything.” The last sentence was slightly rushed, but she could hear the sincerity in his words.

She felt a glimmer of hope at the last bit he said, and taking a shuddering breath, said quietly “Yeah, but what about later? Dipper, this is a dream, the best dream I’ve ever had, but the sucky thing about dreams is you gotta wake up eventually.”

Looking downwards, almost too quiet for him to hear, she said “I know-I know we’ll always be twins and stuff, but I’m worried about if we’ll always be, well….this.”

She looked up to give him another forced smile, but took in a sharp breath. Dipper’s breath was ragged, and his hands around her were shaking as tears were streaming down his face. He pulled her close, and in a voice thick with tears and broken by shuddering breaths, she could hear as he struggled to speak in a relatively-steady voice.

“Mabel, ‘this’ is the best thing that I’ve ever-This is better than…Oh god, Mabel, this is better than I had imagined. You  _understand_  me in a way nobody else has, not Mom, not Dad, not Grunkle Stan, and certainly none of the girls I’ve met before or will meet in our future.” He looked up at her, his cheeks wet with tears that she knew matched her own as he continued.

“Like, you came with me for all those mysteries we investigated up at the Shack; You had my back anytime we were in danger, and we were in danger a lot,” he said, his tone becoming reminiscent as they shared a mutual giggle through the tears. “But the biggest thing is that you know me, better than anyone else, and cared about me as much as I know I care about you.”

He took her hand, looking down on it as he covered it with his other hand and looked up at her. “Lady Mabelton,” he said with a hint of a laugh at the edge, but with a sincerity that was making her mouth dry with anticipation, “You’re my twin, first and foremost, forever and for always.”

She could feel the shadows deepen, the sounds around her becoming muted. Her eyes began to shimmer with tears again, and she clenched them shut, commanding her lip not to tremble yet, not yet, despite feeling like someone took a golf club to her-

“But if you’ll have me, I’d like to be  _yours,_  forever and for always too.”

There was a tinkling noise somewhere in her head, as she cocked her head in disbelief at what Dipper said. He was giving her a look of eager anticipation, which shifted to confusion and then pain as she slapped him with enough force to sting and leave his cheek burning.

“Dipper, what the _hell?_  Why would you say something important like  _that?”_  He gives her a nonplussed look of surprise, and then guilt as he realizes his poor choice of phrasing, but before he can say anything Mabel has dove forward into a hug, squeezing him close and murmuring into his ear.

“I love you, ya big dummy.”

He chuckles, before murmuring back “Love ya to, sis.”

They hug, letting time slip by as they occasionally kiss or nibble each other’s ear and neck, but mostly just snuggle close together in the afternoon sun, enjoying each-other’s warmth. Eventually,they lean back, smiling at each other and stepping off of the bench. A couple that was sitting and enjoying some ice cream nearby glances up at them, but then look back to their snacks wordlessly.

Mabel lets out a sigh, glad she recognized neither of them. While the biggest hurdle had just been leapt, she knew that Dipper and her couldn’t snuggle, kiss, or even hold hands once they got back closer to home. What they had now was too good to risk getting caught and losing it all.

 _Bedrooms, however, are free game,_  she thought with a pleasant warm tingle racing down her body and bringing a hint of pink to her ears.

She steered their meandering walk down a particular direction of the park they had yet to go, and the sun was starting to tickle the tops of the trees on the distant hills. She could hear Dippingsauce sigh beside her, as he saw the sun and said “Well, looks like we might not be able to hit all the rides before the park closes.”

Mabel just grins, and tugs his hand in the direction they’re already heading. “Well, while that is certainly a darn shame, could I by any chance convince you to humor me on one last ride for the afternoon?” she said, her voice slipping into a snobby aristocratic tone that was by no small coincidence reminiscent of Pacifica’s parents.

Dipper gave her a raised eyebrow, but then shrugged, going along with it for now. “Sure, why not. You’ve been itching to take me to whatever this ride is all day.”

Mabel could have sworn steam began to pour from her ears, as she let out a squeak of embarrassment and then leveled an accusing finger at Dipper. “You-You knew all along that I-Gah!” before she began pacing in a little circle, feeling her cheeks begin to blush a bright hue as she rubbed her shoulders and wished fervently for Sweatertown to hide her from her brother.

Dipper put his hands up in defense, though, saying “Hey, I figured it was a surprise, and so, I made sure not to look at the park maps or anything.”

Mabel stopped pacing, and gave him a sheepish grin. “Thanks brobro. I…um, so it was that obvious then?”

He gave her a smile and a wink, saying “Just a bit; Repeatedly avoiding probably a good quarter of the park kinda keyed me in.” Taking in her expression, she can see him grin a bit wider and he steps in front of her to block their path,. “I take it you’ve had this plan in the works for a couple days then?” he says in an inquisitive tone.

Mabel shakes her head, a little too quickly, and begins chewing on the end of a strand of hair as she looks at him. He leans backwards, a bit taken aback at her response. “Oh, wow. Weeks, then?”

Again, Mabel shakes her head, a little squeak of embarrassment coming out as she uses her hair as a curtain in lieu of Sweatertown. At this point, Mabel’s entire head and shoulders feel like they’ve been sunburned as she flushes with embarrassment.

_Come to think of it, though, it might be sunburn too. We were a bit, uh, ‘preoccupied’ coming out of the house today to put on some sunscreen._

She can hear him tapping his finger against his leg, a sign of him being deep in thought, and then hears him stop. He lifts her hair and brushes it off to one side, as he says incredulously “I just remembered there was something in the paper about Watermania getting some new rides at the end of last summer. Has it been that long?”

Mabel spots an opportunity, and after a second of silence rushes out _“PresidentMabelhasnocommentsbyeeeee!”_  as she runs past him towards the kid’s play area and water structures. Dipper laughs, and gives chase, running close behind her.

_Perfect._

She abruptly stops dead in the ankle-deep water, and Dipper splashes up next to her, catching her around the waist and scooping her into the air as she laughs. He sets her down gently, but gives her a puzzled look at her mischevious grin.

“What’s with the face? I don’t trust the face,” he says, smiling but with just a  _tiny_  hint of worry.  Mabel merely smiles, and glances down before looking back up to her brother. Dipper follows her gaze, and notices the enormous red ‘X’ enameled on the waterproof surface.

There is a loud  _CLUNK,_ and Dipper quickly looks up to see a giant red water pail, now filled by a slow trickle of water from an equally-giant yellow faucet, begin to ominously tilt in his direction.

Mabel grabs his shoulders, turning him so she can plant a brief kiss on his lips while standing on tiptoes, before taking an abrupt two steps directly backwards. She can see her brother’s expression, a mixture of shock, annoyance, and amusement, a split second before he is doused in a column of water. She turns and runs off giggling as the waterfall abates, and can hear her brother splutter before giving chase again.

He soon catches up to her, and after giving her a light punch in the arm, they both stop as they come into sight of the ride, and she can hear him chuckle “Ohhh.” Despite his nonchalance, she can see the excited look he gives the ride and her.

“Awesome idea, Mabes,” he says as they walk under the archway marked  _Tunnel of Love_  towards the line’s ride. “I can definitely see why you wanted to save this one for last,” he said, giving her a kiss on the cheek.

_Oh, you haven’t seen anything yet._


	7. Chapter 7

Dipper had to admit; He was impressed. Mabel had managed to keep the primary reason she’d wanted him to come to Watermania so badly a complete secret. While he had restrained himself, with no small amount of difficulty due to how ingrained investigation was into his instincts, and had suspected something was up, he certainly wasn’t expecting, well,  _this._

The ride complex was covered and large; It looked like they’d built a substantial warehouse, decorated lightly on top with some foliage and foam tree trunks, in a mild attempt to make it look like a forest-covered hill. The entrance itself was an unassuming little lazy river, much like the one the Terror had spat them out into, with a yawning lifeguard sitting near a control panel with a trio of buttons on it.

“Um, that’s a, uh, very _comfortable_  boat setup they have there,” he murmured to his sister as he caught sight of one the rafts themselves, as it emerged from the exit. The couple inside it had barely noticed their raft had exited until it bumped against a submerged stop railing, and the men clambered out with a bit of a sheepish smile on their faces towards the lifeguard and the twins before they wandered off with a hand around each-other’s shoulders.

The rafts themselves were painted and shaped to look like Venetian gondolas, albeit shorter and wider and with heavily padded edges at the waterline. Looking back, he could see only two fairly-wide seats in the gondola itself, facing each other just a few feet distant;  _Perfect for gazing into a lover’s eyes, I suppose,_  he thought wryly, before the thought returned a second later to poke him with a reminder: _You and Mabel aren’t lovers, though._

Dipper blushed a bit as an indignant, hopeful bit of him rebelled against logic and common sense. _You mean we aren’t lovers YET._

That thought, and a merry stream of implications and resulting string of momentary minds-eye daydreams about a warm body, writhing in his grasp, hot and responsive to his touch, moaning his name…well, that stream of thought very quickly had Dipper awkwardly coughing and trying to adjust his woefully-insufficient swim trunks again as Mabel clambered into the Gondola..

She then glanced over at his distress, quizzically at first, but then giving him that little taunting and mischievous smile when she noticed his erection. As her arm raised towards him, Dipper could feel an abrupt cold sweat down is back.

_Ohhhh, nonono, Mabel, now’s not a good time, the lifeguard’s right there and looking at us and ohhhh not yet not yet please not yet-_

His sister had apparently heard his unconscious pleas for decorum, or maybe she noticed his face turning cherry red, but in either case her hand made an abrupt veer in direction to one side to grasp his arm, and tug him onto the boat.

As he sat, the lifeguard began reciting the general spiel about safety, keeping arms legs and possessions inside the boat at all times, and to not exit the boat until it came to a complete stop at the end of the ride. Dipper and Mabel shared a brief momentary eye-roll, but nodded, and with the press of a button, the stop rail clacked out of place, and they began to float forward.

The gondola passed through a trio of shimmering tinsel curtains, and briefly looking back, the natural daylight faded as they went around a corner. He was taken aback by the interior, since the appearance outside had been underwhelming. Here, though, the boat was travelling through an area that, through forced perspective, looked like they were on a hill, overlooking a small, sleepy town below.

 _Heck,_  he thought as he watched the light fade to a rosy sunset, lights winking on in the little paper buildings,  _If you squint, add a water tower, and add the split ridge in the distance, it’s not too far off from Gravity Falls._

He smiled, but glancing back to Mabel he saw her staring at him, seemingly ignoring the little picturesque scene next to them. He gave her a smile, and she returned it partially, but he could see something was bothering her; Her shoulders looked stiff, her pose tense, and she had a look in her eyes like she was both ecstatic and terrified.

She stood up abruptly, the boat rocking back and forth a bit, and Dipper let out a “Whoa!” as the gondola rocked, but his sister had ignored the rocking and was now standing in front of him. He could see her shoulders going up and down now as she took little quick breaths, and a second later she closed her eyes, taking a long, steadying breath, before letting it out and opening her eyes.

Dipper had a moment of confusion, and then a white-hot lightning bolt of realization and anticipation as Mabel crouched to kneel on the plastic fake-wood floor of the gondola in front of him. His dick, which had softened significantly when the day-dreaming abated, suddenly reawakened with a vengeance, but Dipper’s mind was a flurry of two streams of thought, fighting each other loudly for his attention as he gave his sister a grin tinged with nervousness, but loaded with unspoken anticipation.

_Mabel, sis, you don’t need to do this, really-_

_-But hey, if you do want to do this, I am 100% on board with this all the way no questions asked-_

_-I don’t want you to feel like you’re obligated to do this since you should know I love you no matter what you do or don’t do-_

_-Man, but if you want to do this, I would love to do this with nobody but you and your amazing body. I mean, hell, you gave me a boner faster than I’d ever had before-_

_-This is so wrong, though, like something you’re never supposed to do-_

_-But it feels so amazingly right, like everything is lining up like it feels like it should-_

_-I don’t want to ever hurt you or break the trust we have-_

_-So please don’t think I hate you and want you to stop-_

_-Don’t do this if you’re not sure-_

_-I love you with no exceptions-_

_-Be true to yourself-_

_-Be my everything-_

_-Please-_

_-Please-_

“Please.”

The roaring of his thoughts culminated in the one little groaned word, and Mabel smiled, and reached up to pull his head down to hers, and brought her beglittered lips up to touch his, gently and almost teasingly, before breaking it. His breathing began to get irregular, short, as he watched her lead kisses down his chin, his bare chest, his little happy trail  _Which was no easy task to grow, mind you,_ before finally kissing the top of his cock through the moist fabric.

His hips twitched as he clenched his eyes shut in ecstasy; He had never gone farther than kissing and a little bit of heavy petting with Pacifica or his other brief attempts at having a girlfriend, and  _this_ was never something he’d have imagined becoming a reality in a thousand years. Hell, this was better than any of his own fantasies of the scenario had ever been, and now there was no worry that something weird, like Grunkle Stan barging in wearing Waddles’ head, was going to happen like what would interrupt his otherwise-happily-erotic dreams.

The baselessly paranoid part of Dipper’s brain poked him to open an eye and glance around quickly for a porcine grandparent. The tunnel scene had shifted to an emulation of a lazy bayou, weeping willows leaning their soft branches into the water on either side and forming a green canopy the boat drifted through.

Mabel gave him another little kiss through the fabric, causing him to twitch again, and then reached up to the zipper and began to slide it down.

Or at least tried to. It was decorative, and she tugged a few times, “hmph!”-ing with frustration after it failed to yield, and Dipper couldn’t help but chuckle. He hooked his thumbs into the sides of his shorts, and began to slide them off; Not without a small amount of effort, due to the tension of the shorts on his bony frame.

As he pulled them down, he slowed, apprehension plaguing him again despite everything that had happened so far. Mabel showed no such hesitation, giving him a slightly annoyed look that was quickly smothered in muted excitement, and she yanked them down to pool around his ankles, revealing his cock to the suddenly-slightly-too-cold air of the ride.

It twitched to one side, and Mabel grabbed it. The feeling of her hot, soft hands on him caused him to twitch again and let out a little happy groan of her name. “Mabel…”

She smiled, leaned up to give him a peck on the cheek, and then leaned back down to engulf him in her mouth.

_Holy MOSES-_

Dipper let out a moan of pleasure, and Mabel replied with a happy hum. As she still had him fully in her mouth, this had the effect of buzzing his cock in an indescribably pleasant way, and he arched his head back, running a hand through her hair before gripping it as his other hand sought a handhold on the smooth side of the gondola.

She made a startled noise as he gripped her hair, and for a second he let go, but before his wrist could migrate away from her, her hand grabbed his, and led him down to the smooth cloth of her bikini top. He smiled, and began running his hand around and along the fabric, feeling her nipple perk up under the fabric as she made a happy moan, again resulting in a buzz on his cock that was heavenly.

He slipped his hand under the fabric, and gave her a gentle squeeze, running his thumb across her nipple and revelling in feeling her shiver with delight. In response, she began running her tongue along the underside of his shaft, causing his hand to freeze as he tried to concentrate all brainpower on burning that feeling into his memory, but more importantly remembering to breath and not pass out.

Then she began sucking, and he could see her hand dive towards her bikini shorts, as her breathing became quicker, panting on his member and occasionally releasing him from her mouth and running her tongue across the tip of his cock before diving back down to engulf him again.

Dipper shuddered, and with a moan of “Oh god, Mabel, I’m-” he could feel his balls clench. Mabel abruptly stopped with her tongue, but continued rubbing herself furiously, and was sucking him harder than before as he came. He could feel the spurting warmth, and could feel her continue to suck, her breathing long and labored as she sucked and swallowed his seed.

After what seemed like a glorious eternity, prolonged by Mabel’s continued sucking even after he stopped cumming, Mabel released him with a wet popping noise, sucking in a breath followed shortly by a giggle. The giggle merged directly into a moan, as she hunched over, her shoulders shaking as Dip could see her hand working furiously beneath the suit.

Unsure of what to do for a moment, Dipper abruptly grabbed his sister’s hand by the wrist, tugging it gently but insistently away from her. As she looked up, saying “Dipperrr…” with a sad longing groan, he knelt down in the rocking gondola, and kissed her on lips still tasting faintly of vanilla-bean.

He could feel her mold to his body, and his spent cock gave an appreciative twitch as their nearly-nude bodies pressed close, indicating that it’d be up for another bout of fun after a quick breather. Dipper hugged Mabel close with one hand, but snaked his other downwards, running a finger down her chest and causing her to moan as he slid under the fabric of the bikini and along the tip of her lips.

 _C'mon porn, tell me all that ‘studying’ was worth it._ He ran a finger along her lips, questing it occasionally between them, each time resulting in her making an appreciative happy noise. Finally, he found what he was looking for, and ran his finger in a little circle around her clit.

The response was immediate, with Mabel choking out  _“Ohgod”_  and smashing her lips against his, thrusting her tongue inside his mouth with a passion that took him momentarily aback. Her hips shook, and her thighs clenched against his hand as he continued to run his finger in little teasing circles, before he finally rubbed it firmly with the pad of the finger.

That hit the spot apparently, as his sister arched backwards, eyes wide open, her mouth open to let out a prolonged, strained “Oooohhhhh” that transitioned into a clenched-teeth squeal of pleasure. He pulled his hand away, encouraged by her own hand as she sat back alongside him on the wide seat. They were both panting, although Mabel seemed like she’d just ran two marathons to Dipper’s one, and she said in a happily exhausted voice “Aw man, Dippingsauce, where did you learn  _that?”_

He looked aside, suddenly slightly embarrassed, and his twin just chuckled and punched him in the arm. “Doofus, I kinda figured you’d seen ‘instructive cinematography.’ But, I mean…wow, did you ever get a chance to practice that in person before?”

Dipper flushed, and with a tight-lipped expression, shook his head. Mabel looked towards him, compassion and a tinge of rising excitement coloring her gasping out “So you mean that was your first-” and letting the unspoken words hang there. Dipper stared at her, abruptly wishing he could have his own sweater and escape this interrogation, but shook his head again before looking down at the false-wood floor.

Mabel let out a happy squeal, and hugged him close, turning to kiss his surprised face on the lips before nuzzling his nose with hers. With a quiet, confident murmur she said “Gotta say, that was both the first time I’ve ever been touched down there by anyone but Yours Truly, but that was also-whooo, that was also the best time I’d been touched down there,  _including_  by Yours Truly.”

Dipper let out a wry grin, but the distant sounds of laughter and splashing brought both of their attentions up to the light at the end of a long straightaway. There was another shimmering impermeable curtain of tinsel, but the corridor was lined with mirrors on all sides, reminding Dipper and Mabel of their discarded clothing and general disheveledness.

The next sixty seconds were a scramble of activity as Mabel tried and only partially succeeded in straightening out her orgasm-induced cowlick, while Dipper nearly capsized the boat trying to struggle back into his squeeze-cage of a swimsuit.

They made it and both sat with barely a few seconds to spare, hands interlaced as they gave each other a loving look, and as they went through the shimmering curtain, the twins leaned in to meet in a warm kiss, savoring it for a moment even as the curtain fell away. The kiss broke off as the sounds and lights of the outside world came blaring back at full force, and they stepped off of the ride, and began to walk towards the rest of the park.

They’d scarcely gotten a few hundred feet from the Tunnel when they heard the echoing cries of _“Doods? Dooooooods? Oh, hey, doods! DOODS!”_  and the commotion from a crowd as Soos’s sounds of “Excuse me” and “Oh, my bad” could be heard as he made his way through the press of bodies. He popped out on the other side, a startlingly horrible Bear-O under one arm, and a “Week of Wet!” watergun the size of a small toddler under the other.

“So, what have you two doods been up to?” Dipper froze, and shared a look of barely-concealed mutual terror with Mabel, as the Tunnel was directly behind them and visible from where they all stood. He could feel his chest start to tighten as his mind raced. _You didn’t check the damn map, and this section is brand new. Oh shit, oh shit, any second now and Soos will see the Tunnel and put two and two together to-_

“We went on Ninjapede Falls!” Mabel exclaimed, startling Dipper out of his tailspin of worry, and he looked over to see her pointing at a black-and-brown rollercoaster that ran through curtains of water. Soos nodded with solemn approval, saying “Oh, good choice doods. I’ve heard that one comes very highly recommended.”

Dipper began to laugh, mostly with relief, and Mabel joined in when they and Soos jumped in terror as the sky flashed, and the darkening clouds boomed with a peal of thunder. A few seconds later, a voice crackled over the loudspeakers, saying tinnily  _“Due to inclement weather, Watermania is now closed. Please file to the nearest exit, remembering any belongings left in lockers. Thank you, and since we are closed for the rest of the season, see you next summer!”_

Soos’ shoulders sagged with disappointment as a spit of rain began to stain the dry pavement, and Dipper could feel a distant pang of regret at not having tried all of the rides this trip. Still, when he looked over at Mabel, that concern washed away with her smile, and she gave a little shrug of her shoulders. “Well brobro, I guess we could always come back next year and make sure we ride _everything.”_

Her tone was innocent, and had Soos nodding in agreement as he fished the car keys out of his pocket, but her tone and the mischievous look in her eyes made it perfectly clear that she included her dear brother in the list of “rides,” and that had his heart racing with anticipation.

As they began the walk to the parking lot, Mabel reached out and grabbed Dipper’s hand; He tensed and started to pull away, what with Soos so near, but then relaxed as he remembered that they did this all the time  _before_  all the wonderful events of today. Ahead of them, Soos called out over his shoulder “Still doods, bit of a bummer that the trip got called on account of rain so soon.” Dipper nodded, but couldn’t help but think:

_You know, I think this excursion was cut short at the perfect time._


	8. Chapter 8

The ride back from Watermania was soothing; Dipper and his sister had to be careful to not linger in each other’s eyes for too long with Soos right there driving, but he was fairly preoccupied with singing along to his Queen CD, and so he and Mabel were able to brush hands a few time with their chauffeur none the wiser. They even sang along when Bohemian Rhapsody inevitably came on, belting out “Beelzebub has a devil put aside for me, for me, for meeeee!” as they pulled off of the interstate.

Soos was leaving after dropping them at their house, but he insisted that they come and visit the Mystery Shack for winter vacation. The twins wholeheartedly agreed, and with a brief honk of the van’s horn, their friend pulled out of the driveway and drove off. Dipper grabbed and squeezed Mabel’s hand one more time, before pulling out his keys and opening the door.

Inside, their mother was sitting in on the couch watching the news, and made a bad joke about “not expecting to get rained on in a waterpark!” The twins groaned appreciatively, and their stomachs did the same when they moseyed on by the kitchen. Their dad had made some kind of tuna-noodle amalgamation that smelled and tasted amazing despite looking like it had already been eaten and regurgitated; Most of their dad’s “meal experiments” ended up like that anyways, delicious yet visually repulsive.

After dinner, though, Dipper had hoped to hang out with Mabel, to be close to her after their experiences together that day, but she had scampered out. As soon as she finished eating, she hastily excused herself from the table before taking a quick shower and then locking herself in her room right away afterwards.

Nonplussed, Dipper cruised around on the internet a bit, double-checked to see if the paranormal forums he frequented had any new sightings in central Oregon, but as he saw the clock tick past ten o’clock, he sighed and shuffled towards his bed, dreading having only one more day to relax before having to go back to his boring job as a retail cashier.

He spared a final glance towards Mabel’s bedroom, where to his surprise her light was still on. He shrugged, though, figuring  _She’s probably telling Candy and Greta about a “new” boyfriend or something,_  he thought with a smile, and he pulled his door almost shut before rolling into bed, his covers forming a warm heap as he fell asleep almost immediately.

He awoke to darkness, and a poking in his side. “Erghph, stoppit. Wannasleep go’way,” he mumbled as a foggy glance at his clock said in red lights  _12:50AM._

He tried to roll back over, but Mabel’s low, insistent voice said “Dip, c’mon, wake up. Please?”

His eyes popped open, and he rubbed some sleep out of them as he spun his legs around to dangle over the side of the mattress. Mabel was sitting in his office chair, wheeled next to his bed, and to his surprise, she still had her bathrobe on?

A little thought began to send pleasant suggestions of what was under said robe, or rather what wasn’t under it. and he could feel his cock twitch sleepily in response, but Dipper’s immediate attention was on his sister’s closed hands, which she held out towards him.

“Close your eyes.”

He did as instructed, and a moment later she said “Alright, open ‘em!” There, on the palms of her outstretched hands, was a tiny Journal 3, looking almost just like he remembered it.

He could feel his throat tighten for a moment, as he said thickly “Aw, Mabes, you, you really didn’t have to-” but he stopped as he held it. It felt weird, different, and he made a puzzled noise as he turned it over in his hands. Mabel broke out into a wide grin, and she explained.

“It’s craft foam! I had to superglue some bits together, and scrounge up a sharpie from that cabinet where mom locked them when I was in 4th grade, but now you have a new mini-journal. You can’t write in this one either  _buuut_  it’s completely waterproof!”

Dipper let out a quiet laugh of amazement, still turning it over in excitement and feeling relief from a last knot of tension he hadn’t even been aware he was still holding on to. His attention shifted, however, when Mabel stood up, shyly looking at him and playing with the cords of the bathrobe’s terrycloth belt.

“Sooo,” she said with a hint of nervousness, “I kinda-sorta-maybe picked out something else while I was going on my ‘Watermania Shopapalooza’ last week.” As she said that, she tugged the robe off and let it fall at her back.

Revealed was a light green teddy, the lacy material cupping and accentuating the curve of her breast as the gauzy material below was plainly transparent and hid nothing. The robe must have still been damp, and he could see where areas of the sheer fabric clung to her form. Below that was a pair of lace panties, a little heart cutout in the middle of the fabric, teasingly revealing an area of smooth skin.

Dipper lost track of his senses for a moment, his attention engrossed in this dream vision of his sister that surpassed anything his mind had been able to conjure before today. The moonlight from the window seemed to frame her lithe form, and she seemed to glow as he watched her.

“So, um, do you like it?”

Dipper said nothing, but temporarily regained motor control as he stood, and pulled her towards him before diving into a kiss. She let out a happy sigh, returning the kiss wholeheartedly, and reaching around to his back with one of her hands. It roamed up under his shirt, feeling the ridges and occasional scars along his back and side, before she ran the hand along his stubbly cheek and reached behind his head to pull Dip deeper into the kiss.

One of Dip’s hands began to run along her back in return, and the other- _Oh, whoops._ The other was occupied with the new journal, which he carefully placed on his desk before using the now-free hand to cup her ass. He loved the feel of her soft, warm skin and the rough thinness of the fabric, and even as he lifted her up he ran a daring finger or two underneath the back of the panties.

She broke their kiss to whisper “Yup, you found it; That’s my butt” before breaking into giggles that Dipper joined in. The giggles gave way to more kisses, their mouths locked as her tongue explored his, and his hands went from her back and ass to running along either side of her chest, ending with cupping her breasts and giving them an experimental rub through the fabric.

Mabel moaned into his mouth, but before he could reach underneath, she had drawn back, breaking their kiss with a mischievous smirk. Dipper grinned back, murmuring “What’s with the face? Should I be worried about this face?”

Mabel grinned, and ran her tongue along her lips, something that Dipper had never consciously fantasized about, but was now 100% certain would feature in large part in most of his “personal time” from this point forward. As she pushed him backwards onto his bed with one hand, she ran the other along her chest, cupping her own breast.

As she did that, she teasingly said “You’re not the only one who uses the computer for ‘research,’” she said, as she brought her hands back to flow along her sides, hooking into the edges of her panties as she tugged them to her knees, shimmying a bit until they fell to the floor. She stepped out of them, and pushing Dipper fully flat against the bed, she got up on the bed and knelt astride him.

Dipper was  _painfully_  erect, rivalling when they were in the Tunnel that afternoon, and his twin certainly wasn’t helping matters as she rocked back and forth, rubbing herself across his suddenly-accursed-and-unwanted pajama pants. As she rubbed herself on him through the thin, infernally-present fleece, Mabel rubbed her breasts through the teddy, the thin material shimmering back and forth as she rocked her hips, and he could hear her let out a little happy moan as she reached in under one of the outfit’s cups to reach her bare skin.

Dipper groaned at the sight and his own sensations, and muttered “Hey Mabes, I think there’s something in the way. You want me to get rid of it?” His voice rose to an unanticipated pleading pitch near the end as she ground especially hard against him, and he thrust his hips upwards in response.

His sister just nodded, but didn’t move off of him. As Dipper leaned forward to remove the offending garment as best as he could, that brought him up nearly chest to chest with Mabel. She gave him a falsely innocent look, one breast popping out of the now-lopsided teddy, and with a grin and a little growl he dove forward, sucking and flicking her nipple with his tongue.

She responded with a moan of her own, her hands suddenly lifting his shirt up to dig her fingers into his back, pulling her against her. He struggled with his pants, before freeing them to around his knees. From there, he had to flail his legs a bit awkwardly for a minute, but the pants slid off to join his sister’s decorative panties on the bedroom floor.

This time it was Mabel’s turn to let out an appreciative growl, and she began to rub against him anew, her wet lips sliding along the underside of his pulsing shaft as they both gasped. Dipper’s mind was becoming white, pleasant noise, and the only word he could whisper out was a muted “Please.”

It was the only word needed.

She shifted her hips forward, and lifted up off of him for a moment. Dip felt his cock twitch as she grabbed it, and guided it to her lips, before she sat down heavily on him, engulfing his length inside her warmth as she let out a little squeak of pleasure, shimmying her hips slightly to fully seat herself on him.

The shock of the amazing feeling partially restarted Dip’s mind, and he moaned out  _“Oh god Mabes,”_ as she began to thrust her hips forwards and back, her hands bracing themselves under his shirt and against his bare chest, the nails tickling and lightly scratching him in the process.

He began to respond in kind, grabbing above her ass and thrusting upwards with his own hips in time, the impact forcing a stilted intake of breath from his sister and a groaning “mmph” from himself with each stroke. The teddy was gorgeous, but now all his mind saw was an impediment to her naked body, and after she helped him out of his shirt, he reached behind her to fumble and unclasp the bra, letting the lacy nothingness fall to the side.

Above him, his sister was now nude, and as close to an angelic form as he could imagine. Her brown curls hung around her head, some plastered to her head and back with sweat, but the others bobbing almost far enough down to provide modesty to her chest. Her breasts were small, but full enough for Dipper’s tastes, and with incredibly responsive nipples that sent Mabel into shivers as he alternately leaned up and sucked each of them.

He had felt shivers and goosebumps down her back when they had first started, but now her back, ass, hips, and thighs were burning, warm and with a thin sheen of exertion on them that matched his own heat. Her taste, as he kissed along her chest and sucked on a finger, was expectedly salty with sweat, but always with that hint of sweetness, that taste that was so completely  _Mabel_  that he couldn’t describe it if he tried.

She began to thrust harder against him, groaning out an increasing-in-pitch “Oooo _ooooooooh-”_  before he could feel her tightening around his cock.

That set him off, and he could feel himself start to clench. “Mabel-” was all he was able to get out before he exploded, feeling his shaft pulse into her. Her groan abruptly shifted upwards to almost a scream, muffled quickly by Dipper as he darted his head up for a kiss, his mind suddenly aware that their parents were asleep just down the hall.

She spasmed around him, her legs jerking and locking around him as his hips thrust upwards even after he spent his load. After her scream faded, he broke the kiss, and Mabel just made a happy “Mm _mmhm,_  oh yessir,  _that_ is a ride Lady Mabeltown would like to ride again once…Whoo, once the world stops spinning.”

He chuckled, and kissed up along her chest to the nape of her neck and under her chin, causing her to shudder and spasm again, and he murmured into her ear “Well, give me a minute to catch my breath and, er,  _recharge_  and the ride should be up and ready for business.”

Mabel murmured a noise of approval into his neck, and slid off of him, laying next to him as he lay back along his bed, resting against the pillow with his arm around her. “I love you Mabes,” he whispered, kissing the top of her head as he enjoyed her warmth.

She sighed happily, and replied “Love you too, Dips.” After a brief pause, she added “And I  _especially_ love your ‘Little Dipper,’” while reaching down to cup his flaccid member and causing him to start.

“Maaaabel,” he said in a voice with more than a bit of a whine in it, and she giggled and threw her arms around him, snuggling against his side and wrapping one of her legs over his. A long day of waterpark fun had combined with their recent coupling, and exhaustion had begun to set in, overruling his protesting libido. He could hear her breathing slow in time with his own, and as he was about to drift unconscious, he heard Mabel, in a voice laced with sleepiness, murmur “G’night brobro.”

He smiled, and the last thing he remembered before drifting asleep was replying “Good night, Mabes.”


	9. Epilogue

The warm morning light tickled Dipper’s eyes, rousing him with a slight groan. As he leaned up, Mabel stirred, her bare back visible peeking out from under a blanket he must have pulled on to them both during the night.

_Wait, Mabel?_

The sudden memories of last night, of their embrace and lovemaking, raced through his mind, and he could feel more than a little bit of arousal in his cock on top of his morning wood. He was looking down at Mabel, when a quiet creak sounded out.

He almost ignored it, because it was just his bedroom door squeaking as a stray breeze from his open window shifted it.

_Oh fuck._

_I forgot to close my door._

Both of their parents were early risers, or at least earlier than the twins; However, a glance to the clock revealed a damning _8:35AM,_  and they were usually up by 8 at the latest. He hopped to the floor, hurriedly pulling on the pair of discarded pajamas as Mabel sat up, murmuring and still half-asleep. “Dip, what’s going on?”

He said nothing, passing her the bathrobe but looking pointedly in the direction of the partially-open door. Mabel followed his gaze, uttering a little squeaked “Oh  _shit.”_  She yanked on the bathrobe, grabbed her discarded lingerie, and after a brief peek out of his doorway, sprinted quietly to her door and darted inside.

Meanwhile, Dipper stood at his door frame, collecting his racing thoughts and straining for a noise of his parents being up.  _Normally one of them is cooking breakfast, so why don’t I hear or smell anything? Heck, today was the big baseball game and I know Mom would have that on if she was up, but I can’t hear the TV either._

Mabel’s door cracked open, and she came out in her typical sleepwear of gym shorts and a baggy shirt that bore a worn _Imaginary friends are the best kind!_ and a little smiling √-1 decorated in faded and patchy glitter. Together they slowly crept down the stairs and into the living room.

The living room was empty, the TV dark, and the kitchen was untouched. Mabel noticed something on the kitchen table, and pointed Dipper towards it. It was a sheet of paper, and Dipper felt his stomach twist in fear as as he grabbed it.

Together, the twins began to read.

_“Dear Mabel and Dipper[…](http://pinewreaths.tumblr.com/post/127357196935/so-what-do-you-think-the-rest-of-the-letter-said)”_

**FIN.**


End file.
